Antibacterial, mechanical and surface properties of Ag-DLC films prepared by dual PLD for medical applications.

Silver doped diamond-like carbon layers were deposited by dual pulsed laser deposition using two KrF excimer lasers. The concentration of Ag, determined by XPS and WDS, moved from zero to ~10at%. We found that the sp2/sp3 ratio, film roughness and the number of droplets (SEM and AFM) increased with increasing silver concentration. The sp3 content measurement (XPS) was influenced by ion cluster surface sputtering and varied from 71.0% (undoped DLC) to 36.2% (for 9.3at% Ag). Transmission was measured on the scale from 200nm to 1100nm, and decreased with increasing silver content. An increase of Ag content has an effect on the decrease of the storage modulus (E') and the indentation hardness (HIT). The highest values HIT=51.9GPa and E'=270.6GPa were measured on a sample with 0at% Ag. The lowest values HIT=26.0GPa and E'=180.2GPa were measured on a sample of 9.3at% Ag. Film adhesion was studied using the scratch test and was up to 20.8N for the highest Ag concentration. The contact angle (CA) measurements for water showed that the CA of Ag-DLC films was higher (78°-98°) that of DLC film (77°). The surface free energy of DLC and of Ag-DLC was about 40mJ·m-2. Antibacterial properties were studied using gram positive and gram negative bacteria. The antibacterial effects increased with the Ag concentration and were ~99.9% after 24h for the layers with the highest silver content (9.3at%). Our results demonstrate that the Ag-doped DLC films are potentially useful biomaterials having both good mechanical properties and antimicrobial characteristics. PRIME NOVELTY STATEMENT: Unique manufacturing technique dual pulsed laser deposition was applied on hydrogen-free diamond-like carbon doped by Ag including topological, physical and antibacterial characterization.

Elemental anomalies in the hippocampal formation after repetitive electrical stimulation: an X-ray fluorescence microscopy study.

Our previous studies carried out on the pilocarpine model of seizures showed that highly resolved elemental analysis might be very helpful in the investigation of processes involved in the pathogenesis of epilepsy, such as excitotoxicity or mossy fiber sprouting. In this study, the changes in elemental composition that occurred in the hippocampal formation in the electrical kindling model of seizures were examined to determine the mechanisms responsible for the phenomenon of kindling and spontaneous seizure activity that may occur in this animal model. X-ray fluorescence microscopy was applied for topographic and quantitative analysis of selected elements in tissues taken from rats subjected to repetitive transauricular electroshocks (ES) and controls (N). The detailed comparisons were carried out for sectors 1 and 3 of the Ammon's horn (CA1 and CA3, respectively), the dentate gyrus (DG) and hilus of DG. The obtained results showed only one statistically significant difference between ES and N groups, namely a higher level of Fe was noticed in CA3 region in the kindled animals. However, further analysis of correlations between the elemental levels and quantitative parameters describing electroshock-induced tonic and clonic seizures showed that the areal densities of some elements (Ca, Cu, Zn) strongly depended on the progress of kindling process. The areal density of Cu in CA1 decreased with the cumulative (totaled over 21 stimulation days) intensity and duration of electroshock-induced tonic seizures while Zn level in the hilus of DG was positively correlated with the duration and intensity of both tonic and clonic seizures.

Antibacterial, cytotoxicity and physical properties of laser--silver doped hydroxyapatite layers.

Hydroxyapatite layers with silver doping from 0.06 at.% to 14 at.% were prepared by laser deposition. The films' physical properties such as morphology, composition, crystallinity, Young's modulus and microhardness were measured. Films were amorphous or polycrystalline in dependence on deposition temperature (from RT to 600 °C). Antibacterial properties were tested using Escherichia coli and Bacillus subtilis cells. The antibacterial efficacy changed with silver doping from 4% to 100%. Cytotoxicity was studied by a direct contact test. Depending on doping and crystallinity the films were either non-toxic or mildly toxic.

Progress of elemental anomalies of hippocampal formation in the pilocarpine model of temporal lobe epilepsy--an X-ray fluorescence microscopy study.

In the present paper, X-ray fluorescence microscopy was applied to follow the processes occurring in rat hippocampal formation during the post-seizure period. In the study, one of the status epilepticus animal models of epilepsy was used, namely the model of temporal lobe epilepsy with pilocarpine-induced seizures. In order to analyze the dynamics of seizure-induced elemental changes, the samples taken from seizure-experiencing animals 3 h and 1, 4, and 7 days after proconvulsive agent administration were analyzed. The obtained results confirmed the utility of X-ray fluorescence microscopy in the research of mechanisms involved in the pathogenesis and progress of epilepsy. The topographic and quantitative elemental analysis of hippocampal formations from different periods of epileptogenesis showed that excitotoxicity, mossy fibers sprouting, and iron-induced oxidative stress may be the processes responsible for seizure-induced neurodegenerative changes and spontaneous recurrent seizures occurring in the chronic phase of the pilocarpine model. The analysis of correlations between the recorded elemental anomalies and quantitative parameters describing animal behavior in the acute period of pilocarpine-induced status epilepticus showed that the areal densities of selected elements measured in the latent period strongly depend on the progress of the acute phase. Especially important seem to be the observations done for Ca and Zn levels which suggest that the intensity of the pathological processes such as excitotoxicity and mossy fibers sprouting depend on the total time of seizure activity. These results as well as dependencies found between the levels of S, K, and Cu and the intensity of maximal seizures clearly confirm how important it is to control the duration and intensity of seizures in clinical practice.

Synchrotron radiation Fourier-transform infrared and Raman microspectroscopy study showing an increased frequency of creatine inclusions in the rat hippocampal formation following pilocarpine-induced seizures.

In the present work, synchrotron radiation Fourier-transform infrared (SRFTIR) and Raman microspectroscopies were used to evaluate a possible role of creatine in the pathogenesis and progress of pilocarpine-evoked seizures and seizure-induced neurodegenerative changes in the rat hippocampal tissue. The main goal of this study was to identify creatine deposits within the examined brain area, to analyze their frequency in epileptic animals and naive controls and to examine correlations between the number of inclusions in the hippocampal formation of epileptic rats and the quantitative parameters describing animal behavior during 6-h observation period after pilocarpine injection. The presence of creatine in the brain tissue was confirmed based on the vibrational bands specific for this compound in the infrared and Raman spectra. These were the bands occurring at the wavenumbers around 2800, 1621, 1398, and 1304 cm(-1) in IR spectra and around 1056, 908 and 834 cm(-1) in the Raman spectra. Creatine was detected in eight of ten analyzed epileptic samples and in only one of six controls under the study. The number of deposits in epileptic animals varied from 1 to 100 and a relative majority of inclusions were detected in the area of the Dentate Gyrus and in the multiform hippocampal layer. Moreover, the number of creatine inclusions was positively correlated with the total time of seizure activity.

The comparison of Health-Related Quality of Life (HRQL) in patients with GERD, peptic ulcer disease and ulcerative colitis.

PURPOSE: The aim of the study was to compare HRQL in patients with three common gastroenterological chronic conditions: gastroesophageal reflux disease (GERD), peptic ulcer disease (PUD) and ulcerative colitis (UC), as well as to assess the correlation between HRQL scores and the disease activity in patients with ulcerative colitis. MATERIAL AND METHODS: The study group comprised of 45 patients with GERD, 35--with PUD and 30--with UC. Among patients with UC, 7 were in remission, 13--in mild active and 10--with severe phase of the disease, according to Rachmilewitz. HRQL was assessed using 8 domains of Polish version of 36-Item Short Form Survey (SF-36). RESULTS: The highest mean HRQL scores in all groups were obtained in physical and social functioning SF-36 domains. Among patients with GERD and PUD the worst HRQL results were noted in bodily pain subscale; in patients with UC--in general health perception subscale. UC patients with remission showed significantly higher HRQL scores compared with those with mild active and severe phase of the disease; especially in social functioning, mental health and vitality (p < 0.001). Patients with severe UC clinical course had mean HRQL scores statistically lower than those with mild active disease only in vitality and social functioning domains. Mean SF-36 bodily pain parameters were significantly lower in GERD and PUD compared with UC. CONCLUSIONS: All the evaluated diseases have a significant negative impact on patients' HRQL parameters, which needs to be considered in those diseases management. The severity of UC clinical course contributes to impaired HRQL.

[A new model of computerized encephalovolumeter for monitoring of acute cerebrovascular insufficiency]. / Nowy model skomputeryzowanego encefalowolumometru do monitorowania ostrej niedomogi krazenia mózgowego.

A new model of the computerized encephalovolumeter (EVM.IR) is presented. Infrared light is used as an information carrier enabling to follow the dynamics of intracerebral equilibrium and blood flow disorders. The authors suggest that this model would help clinical examination in the acute cerebral flow failure, and increase better evaluation of the efficiency of drugs improving cerebral blood flow. It should also help to foresee the outcome and prognosis. A new model of EVM.IR and its programs require further constructional and experimental studies before the routine use at ICUs.

Comparative light microscopical and X-ray microanalysis study of barium granuloma.

A barium granuloma occurring in the gastric wall was examined by various light microscopical methods and with the scanning electron microscope in association with an energy dispersive x-ray spectrometer. Barium sulphate is present in the form of a slightly granular, yellowish and greenish substance within the cytoplasm of macrophages, and shows no birefringence. Needle-shaped and rhomboid birefringent crystals are rich in magnesium and silicon, and most probably present talc crystals, one of the admixtures in common commercial preparations used for contrast x-ray examination of the gastrointestinal tract, rather than crystals of barium sulphate proper as erroneously interpreted in the literature.

Hand skill measurement: a gauge for treatment.

Objective measurements of performance are vital with the increasing necessity to justify the need for occupational therapy services, and to conduct studies that measure the effectiveness of treatment procedures. This paper reports on a measurement of hand skill that was standardized by comparing hand skill performance among the able-bodied, or normal, population. The performance on this test o patients with various types of disabilities and the implications for treatment are discussed. For the paraplegic, the hand skill test indicates the need for occupational therapy services; for the quadriplegic, the test measures the effectiveness of functional orthotic devices; and for the hemiplegic, the hand skill test determines the potential for success in one aspect of self-care, dressing.